Example #1
0
int main()
{
    slong iter;
    flint_rand_t state;

    flint_printf("pow_acb_series....");
    fflush(stdout);

    flint_randinit(state);

    /* compare with exp/log */
    for (iter = 0; iter < 10000 * arb_test_multiplier(); iter++)
    {
        slong prec, trunc;
        acb_poly_t f, g, h1, h2;
        acb_t c;

        prec = 2 + n_randint(state, 200);
        trunc = n_randint(state, 20);

        acb_poly_init(f);
        acb_poly_init(g);
        acb_poly_init(h1);
        acb_poly_init(h2);
        acb_init(c);

        /* generate binomials */
        if (n_randint(state, 20) == 0)
        {
            acb_randtest(c, state, prec, 10);
            acb_poly_set_coeff_acb(f, 0, c);
            acb_randtest(c, state, prec, 10);
            acb_poly_set_coeff_acb(f, 1 + n_randint(state, 20), c);
        }
        else
        {
            acb_poly_randtest(f, state, 1 + n_randint(state, 20), prec, 10);
        }

        acb_poly_randtest(h1, state, 1 + n_randint(state, 20), prec, 10);

        acb_randtest(c, state, prec, 10);
        acb_poly_set_acb(g, c);

        /* f^c */
        acb_poly_pow_acb_series(h1, f, c, trunc, prec);

        /* f^c = exp(c*log(f)) */
        acb_poly_log_series(h2, f, trunc, prec);
        acb_poly_mullow(h2, h2, g, trunc, prec);
        acb_poly_exp_series(h2, h2, trunc, prec);

        if (!acb_poly_overlaps(h1, h2))
        {
            flint_printf("FAIL\n\n");

            flint_printf("prec = %wd\n", prec);
            flint_printf("trunc = %wd\n", trunc);

            flint_printf("f = "); acb_poly_printd(f, 15); flint_printf("\n\n");
            flint_printf("c = "); acb_printd(c, 15); flint_printf("\n\n");
            flint_printf("h1 = "); acb_poly_printd(h1, 15); flint_printf("\n\n");
            flint_printf("h2 = "); acb_poly_printd(h2, 15); flint_printf("\n\n");

            abort();
        }

        acb_poly_pow_acb_series(f, f, c, trunc, prec);

        if (!acb_poly_overlaps(f, h1))
        {
            flint_printf("FAIL (aliasing)\n\n");
            abort();
        }

        acb_poly_clear(f);
        acb_poly_clear(g);
        acb_poly_clear(h1);
        acb_poly_clear(h2);
        acb_clear(c);
    }

    flint_randclear(state);
    flint_cleanup();
    flint_printf("PASS\n");
    return EXIT_SUCCESS;
}
int main()
{
    slong iter;
    flint_rand_t state;

    flint_printf("gamma_upper_series....");
    fflush(stdout);

    flint_randinit(state);

    for (iter = 0; iter < 1000 * arb_test_multiplier(); iter++)
    {
        slong m, n1, n2, bits1, bits2, bits3;
        acb_poly_t S, A, B, C;
        acb_t s, t, c;
        int regularized;

        regularized = n_randint(state, 3);

        bits1 = 2 + n_randint(state, 200);
        bits2 = 2 + n_randint(state, 200);
        bits3 = 2 + n_randint(state, 200);

        m = 1 + n_randint(state, 10);
        n1 = 1 + n_randint(state, 10);
        n2 = 1 + n_randint(state, 10);

        acb_poly_init(S);
        acb_poly_init(A);
        acb_poly_init(B);
        acb_poly_init(C);
        acb_init(s);
        acb_init(t);
        acb_init(c);

        acb_poly_randtest(S, state, m, bits1, 3);
        acb_poly_randtest(A, state, m, bits1, 3);
        acb_poly_randtest(B, state, m, bits1, 3);
        acb_randtest(s, state, bits1, 3);

        acb_hypgeom_gamma_upper_series(A, s, S, regularized, n1, bits2);
        acb_hypgeom_gamma_upper_series(B, s, S, regularized, n2, bits3);

        acb_poly_set(C, A);
        acb_poly_truncate(C, FLINT_MIN(n1, n2));
        acb_poly_truncate(B, FLINT_MIN(n1, n2));

        if (!acb_poly_overlaps(B, C))
        {
            flint_printf("FAIL (consistency)\n\n");
            flint_printf("regularized = %d\n\n", regularized);
            flint_printf("S = "); acb_poly_printd(S, 15); flint_printf("\n\n");
            flint_printf("A = "); acb_poly_printd(A, 15); flint_printf("\n\n");
            flint_printf("B = "); acb_poly_printd(B, 15); flint_printf("\n\n");
            flint_printf("C = "); acb_poly_printd(C, 15); flint_printf("\n\n");
            flint_abort();
        }

        /* f(h(x)) = -exp(-h(x)) h(x)^(s-1) */
        acb_poly_neg(C, S);
        acb_poly_exp_series(C, C, n1, bits2);
        acb_sub_ui(t, s, 1, bits2);
        acb_poly_pow_acb_series(B, S, t, n1, bits2);
        acb_poly_mullow(C, C, B, n1, bits2);
        acb_poly_neg(C, C);

        if (regularized == 0)
        {
            /* integral(f(h(x)) h'(x))' = f(h(x)) h'(x) */
            acb_poly_derivative(B, S, bits2);
            acb_poly_mullow(C, C, B, n1, bits2);

            acb_poly_truncate(C, n1 - 1);
        }
        else if (regularized == 1)
        {
            /* (integral(f(h(x)) h'(x)) / c)' = (f(h(x)) h'(x)) / c */
            acb_poly_derivative(B, S, bits2);
            acb_poly_mullow(C, C, B, n1, bits2);

            acb_gamma(c, s, bits2);
            acb_poly_scalar_div(C, C, c, bits2);

            acb_poly_truncate(C, n1 - 1);
        }
        else if (regularized == 2)
        {
            /* (h(x)^-s integral(f(h(x)) h'(x)))' =
             * h(x)^-(s+1) (h(x) f(h(x)) - s integral(f(h(x)) h'(x))) h'(x) */
            acb_poly_t D;
            acb_poly_init(D);

            acb_poly_derivative(B, S, bits2);
            acb_poly_mullow(D, C, B, n1, bits2);
            acb_poly_integral(D, D, bits2);
            acb_poly_scalar_mul(D, D, s, bits2);
            acb_poly_mullow(C, C, S, n1, bits2);
            acb_poly_sub(D, C, D, bits2);

            acb_add_ui(t, s, 1, bits2);
            acb_neg(t, t);
            acb_poly_pow_acb_series(B, S, t, n1, bits2);

            acb_poly_mullow(C, D, B, n1, bits2);

            acb_poly_derivative(B, S, bits2);
            acb_poly_mullow(C, C, B, n1, bits2);

            acb_poly_truncate(C, n1 - 1);

            acb_poly_clear(D);
        }

        acb_poly_derivative(B, A, bits2);

        if (!acb_poly_overlaps(B, C))
        {
            flint_printf("FAIL (derivative)\n\n");
            flint_printf("regularized = %d\n\n", regularized);
            flint_printf("S = "); acb_poly_printd(S, 15); flint_printf("\n\n");
            flint_printf("A = "); acb_poly_printd(A, 15); flint_printf("\n\n");
            flint_printf("B = "); acb_poly_printd(B, 15); flint_printf("\n\n");
            flint_printf("C = "); acb_poly_printd(C, 15); flint_printf("\n\n");
            flint_abort();
        }

        acb_hypgeom_gamma_upper_series(S, s, S, regularized, n1, bits2);

        if (!acb_poly_overlaps(A, S))
        {
            flint_printf("FAIL (aliasing)\n\n");
            flint_printf("regularized = %d\n\n", regularized);
            flint_printf("S = "); acb_poly_printd(S, 15); flint_printf("\n\n");
            flint_printf("A = "); acb_poly_printd(A, 15); flint_printf("\n\n");
            flint_abort();
        }

        acb_poly_clear(S);
        acb_poly_clear(A);
        acb_poly_clear(B);
        acb_poly_clear(C);
        acb_clear(s);
        acb_clear(t);
        acb_clear(c);
    }

    flint_randclear(state);
    flint_cleanup();
    flint_printf("PASS\n");
    return EXIT_SUCCESS;
}